Documents disponibles écrits par cet auteur

Impact of classical assumptions in modelling a microchannel gas cooler / Santiago Martínez-Ballester in International journal of refrigeration, Vol. 34 N° 8 (Décembre 2011) 

Public ISBD [article]  in International journal of refrigeration > Vol. 34 N° 8 (Décembre 2011) . - pp. 1898–1910 Titre : Impact of classical assumptions in modelling a microchannel gas cooler Titre original : Impact des hypothèses classiques sur la modélisation d'un refroidisseur de gaz à microcanaux Type de document : texte imprimé Auteurs : Santiago Martínez-Ballester, Auteur ; José-M. Corberán, Auteur ; José Gonzálvez-Maciá, Auteur Année de publication : 2012 Article en page(s) : pp. 1898–1910 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Modelling  Simulation  Microchannel  Fin  Gas  cooler Résumé : Most of the current air-to-refrigerant heat exchanger models use the classic ɛ-NTU approach, or some of its assumptions. These models do not account for longitudinal heat conduction in the tube and the fin, and the heat conduction between different tubes. This paper presents a more fundamental numerical approach to heat exchanger modelling which takes into account the 2D longitudinal heat conduction in any element, does not apply the fin theory, and captures a more detailed representation of air properties. Using the fundamental numerical approach, the paper assesses the impact of the traditional heat exchanger model assumptions when modelling a microchannel gas cooler working with CO2. The study revealed significant differences in capacity predictions depending on the ɛ-NTU relationship adopted. Large errors in capacity prediction of individual tubes occurred due to the adiabatic-fin-tip assumption when the neighbouring tubes were of different temperature. ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700711001782# [article] Impact of classical assumptions in modelling a microchannel gas cooler = Impact des hypothèses classiques sur la modélisation d'un refroidisseur de gaz à microcanaux [texte imprimé] / Santiago Martínez-Ballester, Auteur ; José-M. Corberán, Auteur ; José Gonzálvez-Maciá, Auteur . - 2012 . - pp. 1898–1910. Génie mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 34 N° 8 (Décembre 2011) . - pp. 1898–1910 Mots-clés : Heat  exchanger  Modelling  Simulation  Microchannel  Fin  Gas  cooler Résumé : Most of the current air-to-refrigerant heat exchanger models use the classic ɛ-NTU approach, or some of its assumptions. These models do not account for longitudinal heat conduction in the tube and the fin, and the heat conduction between different tubes. This paper presents a more fundamental numerical approach to heat exchanger modelling which takes into account the 2D longitudinal heat conduction in any element, does not apply the fin theory, and captures a more detailed representation of air properties. Using the fundamental numerical approach, the paper assesses the impact of the traditional heat exchanger model assumptions when modelling a microchannel gas cooler working with CO2. The study revealed significant differences in capacity predictions depending on the ɛ-NTU relationship adopted. Large errors in capacity prediction of individual tubes occurred due to the adiabatic-fin-tip assumption when the neighbouring tubes were of different temperature. ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700711001782#

Influence of the source and sink temperatures on the optimal refrigerant charge of a water-to-water heat pump / José-M. Corberán in International journal of refrigeration, Vol. 34 N° 4 (Juin 2011) 

Public ISBD [article]  in International journal of refrigeration > Vol. 34 N° 4 (Juin 2011) . - pp. 881-892 Titre : Influence of the source and sink temperatures on the optimal refrigerant charge of a water-to-water heat pump Titre original : Influence des températures de la source et du puits thermique sur la charge en frigorigène optimale d'une pompe à chaleur eau-eau Type de document : texte imprimé Auteurs : José-M. Corberán, Auteur ; Israel Martínez-Galván, Auteur ; Santiago Martínez-Ballester, Auteur Année de publication : 2011 Article en page(s) : pp. 881-892 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Modelling  Heat  pump  Chiller  Refrigerant  Charge  Distribution  Solubility  Oil Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This paper presents the results of a study carried out to elucidate the influence of the source and sink temperatures on the optimal charge of a propane water-to-water 16 kW heat pump which does not incorporate any liquid receiver. The unit had been fully tested along a previous experimental study, at various refrigerant charges and different condensing temperatures. A detailed mathematical model was then employed to simulate the unit performance. The predicted results were in very good agreement with the experiments, and furthermore, showed the same trends found in a similar unit tested at the KTH (Sweden) when the evaporation temperature was progressively decreased. Then, the model was employed to study the influence of the source and sink temperatures on the optimal charge of the unit. The simulation showed that the great variation of the optimal charge with the variation of the evaporation temperature is mainly due to the variation of the amount of refrigerant in the compressor oil. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700711000223 [article] Influence of the source and sink temperatures on the optimal refrigerant charge of a water-to-water heat pump = Influence des températures de la source et du puits thermique sur la charge en frigorigène optimale d'une pompe à chaleur eau-eau [texte imprimé] / José-M. Corberán, Auteur ; Israel Martínez-Galván, Auteur ; Santiago Martínez-Ballester, Auteur . - 2011 . - pp. 881-892. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 34 N° 4 (Juin 2011) . - pp. 881-892 Mots-clés : Modelling  Heat  pump  Chiller  Refrigerant  Charge  Distribution  Solubility  Oil Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This paper presents the results of a study carried out to elucidate the influence of the source and sink temperatures on the optimal charge of a propane water-to-water 16 kW heat pump which does not incorporate any liquid receiver. The unit had been fully tested along a previous experimental study, at various refrigerant charges and different condensing temperatures. A detailed mathematical model was then employed to simulate the unit performance. The predicted results were in very good agreement with the experiments, and furthermore, showed the same trends found in a similar unit tested at the KTH (Sweden) when the evaporation temperature was progressively decreased. Then, the model was employed to study the influence of the source and sink temperatures on the optimal charge of the unit. The simulation showed that the great variation of the optimal charge with the variation of the evaporation temperature is mainly due to the variation of the amount of refrigerant in the compressor oil. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700711000223